PROJECT SUMMARY: The India Human Development Survey III, will trace, locate and re-interview households that participated in waves 1 and 2 of the India Human Development Survey (IHDS), conducted in 2004-05 and 2011-12, respectively. This proposed wave 3 of a nationally representative multi-topic survey samples more than 41,000 households comprising over 200,000 individuals across India. India has undergone a dramatic transformation over the past 20 years. Poverty has declined, education levels have increased, and vast social programs have been instituted. Today?s India stands at the threshold of an epidemiological transition wherein it is facing the growth of non-communicable diseases, while still being buffeted by the threat of infectious diseases. Its health systems are grappling with these dual demands notwithstanding the expansion in public and private health insurance programs. A third round of IHDS slated to be carried out in 2018-19 will allow researchers worldwide to study the ways in which health and household behaviors in India respond to these vast changes. The IHDS surveys comprise a premier public resource for researchers interested in global health in a transitional society comprising nearly a fifth of the global population. Between July 1, 2015 and December 19, 2016, in the Data Sharing for Demographic Research (DSDR) archive of 375 NIH-funded studies, IHDS- I was the second most downloaded survey (2300 users) and IHDS-II the third most downloaded survey (1629 users). Overall, since the release of IHDS-I in 2008, more than 9000 unique users have downloaded IHDS data files. When combined with a third round of the survey, these data will constitute the most comprehensive source for understanding how vast economic and political transformations shape health outcomes and behaviors, and allow for research on the evolution of health over the life course. In addition to replicating measures taken over the previous 15 years, several features of the proposed data collection project represent innovations by providing new data on topics of relevance to global health.